This invention relates generally to conveyor systems and, in particular to conveyors used to unscramble articles received in random order and orient and align the articles in a single file. The invention is particularly adapted for use upstream of an induction system but may have other applications.
Many conveyor operations, especially those used in article distribution centers, receive a variety of articles varying in weight, height, length and depth. These articles are unloaded from trucks en masse and placed on the conveyor system. Once upon the conveyor, the articles are forwarded to a central area in random order and orientation. At this point in the conveyor operation, it becomes necessary to orient and align the articles in a single file for further processing. Normally, such further processing includes scanning a barcode attached to the surface of each article. This barcode contains information which identifies the destination of the article. After scanning the articles, they are sorted using a sortation conveyor to discrete departure destination areas. Once in a particular departure destination, the articles are loaded into a truck or other form of transportation and shipped to their final destination. Failure to properly unscramble and singulate articles prior to reaching the scanner results in shipment of articles to an incorrect destination and reduces the efficiency of the distribution process.
Unscrambling and aligning conveyors normally utilize skewed rollers which transport articles longitudinally and laterally toward one side of the conveyor. Often, such systems utilize a discrete number of "zones" which are driven at progressively faster speeds in order to unscramble and align the articles. Each zone of the unscrambling and aligning conveyor is driven by a separate motor and dedicated drive mechanism. Consequently, such unscrambling and aligning conveyors are often expensive and are susceptible to failure due to the number of different motors and drive systems necessary to operate the unit. Thus, these conveyors require frequent maintenance, which in turn increase the costs associated with the distribution process.
Furthermore, existing unscrambling and aligning conveyors do not effectively eliminate the occurrence of "side-by-side" articles. "Side-by-side" articles, as they are referred to in the industry, are two or more articles which are positioned laterally adjacent along the unscrambling and aligning conveyor and remain so when transferred to the discharge end. The existence of "side-by-sides" interferes with the scanning procedure, insofar as the scanner is incapable of scanning more than one package simultaneously. If such "side-by-sides" are detected, they are manually removed from the conveyor system and placed in a recirculation line, thereby decreasing the throughput of the conveyor system as a whole. If undetected, one of the articles, specifically, the one which is not detected by the scanner, is often sorted along with the adjacent article and subsequently shipped to an incorrect destination. Furthermore, "side-by-sides" often generate jams during the sortation procedure, and thereby reduces the throughput, or articles sorted per unit time, of the distribution center.
Additionally, existing conveyors systems often undergo updating to generate a higher throughput. For example, an existing conveyor system may have the sortation system replaced in order to utilize new technology and thereby increase the efficiency of the system as a whole. Consequently, it often becomes necessary to replace an existing unscrambling and aligning conveyor with one having the ability to handle a larger volume of parcels at a higher speed. Heretofore, replacement of the unscrambling and aligning conveyor has presented problems for the industry. Normally, replacing an unscrambling and aligning conveyor required the same to be torn out and replaced with the updated conveyor. This is a great expense in terms of both cost and downtime.
Also, it is relatively common to add an unscrambling and aligning conveyor to an existing conveyor system. For example, it may be desirable to add an unscrambler upstream of an induction system in order to significantly reduce the number of side-by-side articles fed to the induction system. Such side-by-side articles tend to interfere with proper operation of the induction system and have previously required an operator to manually remove such packages. In such instances, a length of conveyor must be torn out and replaced with an unscrambling and aligning conveyor. The procedure of adding an unscrambling and aligning conveyor may also be costly, resulting in a large amount of downtime as the existing conveyor section must be completely torn out and the unscrambling and aligning conveyor installed.
Consequently, there exists a need for an unscrambling and aligning conveyor which can effectively singulate a large volume of packages delivered thereto in a close packed order at a rate which is commensurate with the existing high speed conveyor equipment, and can be retrofitted onto an existing conveyor system with a minimal amount of labor and changeover costs.